Railway signaling.



H. A. WALLACE. RAILWAY SIGNALING. APPLICATION HLED mun, 1914.

1,213,309. Patented J... 23, 1917.

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Releasiny WITNESSES A INVENTOR W W4 476M524, @w. (5. m

UNITED STATES PATENT OFFICE.

HERBERT A. WALLACE, F NEW.YORK, N. Y., ASSIG-NOR TO THE UNION SWITCH &

SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENN- SYLVANIA.

RAILWAY SIGNALING.

Specification of Letters Patent.

' Patented Jan. 23, 1917.

of single track over which trafiic moves in.

both directions, such for example, as stretches of single track between passing sidings.

I will describe one form of signaling system embodying my invention, and will then point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic view showing a stretch of single track having applied thereto one form of signaling system embodying my invention.

Referring to the drawin A-B is a stretch of single track between two passing sidings E and F, over which stretch traiiic moves in both directions. Trafiic through this stretch from east to west is governed by. signals S, S and S located at intervals through the stretch, and traflic through the stretch from west to east is governed by other signals S S and S", located also at intervals through the stretch.

The stretch AB is divided by insulated joints 3 into several successive sections AC, CD and D-B, and as .here shown a pair of opposing signals is located near each junction of adjacent sections, although I do not wish to be limited to this particular location of the signals. Each section is provided with one or more track circuits includ;

ing track relays for the control of the signals. As here shown, each section is divided by insulated joints 3 into two sub-sections, and each sub-section is provided with a separate track circuit. For example, section AC is divided into two sub-sections A-H and HC. Each track circuit comprises the rails of the sub-section, a battery 6, and a track relay, the latter being designated by thereference character T with the same exponent as that of the adjacent signal which governs trafiic through the corre sponding sub-section.

" For each signal I provide a signal relay for the control thereof, which relays are designated in the drawing by the reference character R with an exponent corresponding to the exponent of the signal which the relay controls. Each signal is provided with a circuit which is controlled by the corresponding signal relay. For example, the circuitfor signal S is from battery 10 through wires 11, 12, 13, and 27, contact 28 of relay R wire 29, mechanism of signal S wires 30 and '39, common wire 0 to battery 10. Each of the other signals is provided with a circuit similar to that for signal S 1 Each signal relay (except relays R and R is controlled by both track relays for the section through which the corresponding signal governs trafiic, and also by a circuit controlling contact K operated by the signal next in advance governing traffic in the same direction, which contact is closed or open according as the signal which operates it indicates clear or danger. For example, relay R, which controls signal S,

is provided with the following circuit from battery 10, through wires 11, 4 and 5, contact K wire 6, contact 18 of track relay T", wire 19, contact 20 of track relay T, wire 21, signal relay R, wires 22 and 23, and common wire 0 to battery 10. The circuits for signal relays R R and R are similar to that just traced for relay R. The circuits for signal relays It and R are similar to that just traced for relay R except that they are controlled only by the track relays for sections DB and AC respectively, there being, in the form of signaling here shown, no signal operated contacts to control these circuits.

It will be seen that as thus far described, each signal relay is controlled by the track relays for the section through which the corresponding signal governs traffic, and also by a contact operated by the signal next in advance governing traflic in the same direction. Hence, as a train enters the stretch from either end, all the signals governing trafiic through the stretch in the'direction opposite to that in which the train is moving will change to danger indication. Also, with the apparatus thus far described, as ai proceeds thr ugh the tret h, h gnals in its rear governing trafiic in the direction of movement of the train would change o dange nd ca ion and-r ma n. there until the train leaves the stretch. Means are provided, however, for at times rendering each signal-operated contact inefiective to control the signal relay next in the rear,'s0 that as a train proceeds through the stretch the signals in the rear of the train may change to clear indication when the train has left the portions of the stretch which they immediately govern, thereby permitting a following train to proceed through the stretch at a safe distance from the first train. This means, as here shown, is a branch around the signal-operated contact,

which branch is controlled by an auxiliary relay. These auxiliary relays are in the drawing designated by the reference character X. with'the same exponent as that of the corresponding signal. For example, the branch around contact K operated by signal S is from wire 4 through wire 24:, contact 25 of auxiliary relay X wire 42, to wire 6. It will be seen that each auxiliary relay, when energized, closes the branch around the contact operated by the corre sponding signal, and thus renders such contact ineffective to control the signalrelay for the signal next in the rear. No auxiliary relays are provided for signals S and S because in the illustrated embodiment of my invention these signals are not provided with contacts to control signal relays.

Each auxiliary relay X is provided with a pick-up circuit and also with a holding circuit. For example, the pick-up circuit for relay X is from battery 10 through wires 11, 12, 13, 14c and 15, back contact 16 of track relay T wires 17 and 31, relay X wires 32 and 33, contact 3% of relay R wires 35 and 39, common wire 0 to battery 10. It will be seen that this circuit is closed only when track relay T is open and signal relay R is closed; consequently, this circuit can be closed only when a westbound train enters sub-section DL. The holding circuit for auxiliary relay X is the same as the pick-up circuit as far as and including wire 32, then through wire 36, contact 37 of. relay X wire 38 to Wire 39. It will be seen that this circuit can be closed only when relay X is energized. The holding circuit for relay X is provided with abranch around contact 16, which branch includes back contact 40 of relay R this branch being from wire 12, through wire 39, back contact 40 to relay R and wire 41 to wire 31. By means of this branch relay X will be held closed as long as relay R is open, even though track relay T closes when the westbound train passes out of subsection DL. Each auxiliary relay is provided with a pick-up circuit and a holding circuit which circuits vare similar to those just traced for relay X In order to simplify the drawing, however, I have omitted these circuits for auxiliary relays X and X.

The operation of the apparatus during the passage of a westbound car or train through the stretch AB is as follows: As the train enters sub-section BM, it opens track relay T, thereby opening at contact 20 the circuit for signal relay R, which in turn causes signal S to change to danger indication. The opening of contact 43 of track relay T opens the circuit of signal relay R", which latter causes signal S to change to danger. As soon as signal S reaches the danger position, contact K operated thereby opens the circuit of signal relay R thereby causing signal S to assume danger indication, and this latter sig nal in turn through the medium of contact K operated thereby causes the opening of relay R whereupon signal S assumes danger indication. It will be seen, therefore, that as soon as the train enters sub-section B-M, all signals governing trafiic in the direction opposite to the direction of movement of the train change to danger indication. As the train enters sub-section M-D, it opens track relay T", but this has no effect on the signals, because contacts 18 and 4A of this relay control the same circuit as contacts 20 and 43 of track relay T; the closing of back contact 16 of relay T does not close the pick-up circuit for relay X", because this circuit is open at contact 34 of relay it". As the train enters sub-section DL, it opens track relay T thereby opening at contact 45 the circuit for signal relay R which in turn causes signal S to change to danger indication. The opening of contact 46 of track relay T opens at this point the circuit for relay R, but this has no influence on the signals, because this circuit was already open at contact K of signal S. The movement of the signal S to danger, opens contact K and this would hold open the circuit for signal relay H were not auxiliary relay X closed at this time. This auxiliary relay is closed in the following manner: During the interval between the closing of back contact 16 of track relay T and the opening of front contact 34: of signal relay R the pick-up circuit of relay X is closed. This interval will ordinarily be sul'licient to enable auxiliary relay X to pick-up and to thereby close its holding circuit, but, if necessary, relay B may be made slow-releasing, thereby giving a considerable interval of time during which the pick-up circuit is closed. When the entire train has left sub-section .M-D, the closing .of track relay.T closes the circuit for signal relay B so that signal S then changes to clear indication, thereby permitting a following westbound car or train to enter the stretch. The closing of track relay T also closes at contact 44 the circuit for signal relay It, so that signal S then changes to clear indication. When the train passes out of sub-section D-L, the closing of track relayT opens one branch of the holding circuit for auxiliary relay X, but the other branch of this circuit remains closed at contact 40 of relay R so that relay X continues to be closed. As the train enters sub-section L-C, the opening ofi track relay T opens at this point the circuits for signal relays R and R", but otherwise it'has no effect on the apparatus. As the train enters sub-section C-H, the opening of track relay 1 opens the circuit of relay R which in turn causes signal S to assume danger indication, but the opening of track relay T also causes auxiliary relay X to be closed, so that when the entire train has left sub-section LC signal relay R closes, thereby causing signal S to assume clear indication. The movement of signal S to the'clear position closes contact K so that the circuit for signal relay R is then closed independently of auxiliary relay X which latter relay opens as soon as relay R closes.

The operation of the apparatus during the passage of an eastbound car or train through the stretch is similar to that just explained for the passage of a westbound car or train.

Although I have herein shown and described only one form of signaling system embodying my invention, it is understood that various changes and modifications may be made therein within the scope of 'the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, a stretch of railway track divided into a plurality of sections, a pair of opposing signals located substantially'at each junction of adjacent sections for governing traflic in opposite directions, a signal relay forthe control of each signal, track circuits for the sections, each including a track relay for controlling the signal relay for each signal governing trafiic through the section; means for controlling each signal relay by the signal relay for the signal next in advance governing traflic in the same direction, an auxiliary relay for each signal relay adapted when energized to render the latter inefl ective to control the signal relay for the signal next in the rear, a pick-up and a holding circuit for each auxiliary relay, each ick-up circuit including aback contact 0 a track relay for the section through which the corresponding signal governs traflic, and a front contact of the corresponding signal relay, and each holding circuit including a front contact of the auxiliary relay and the said back contact of the track relay. and a source of current.

2. In combination, a stretch of railway track divided into a plurality of sections, a pair of opposing signals located substantially at each junction of adjacent sections I for governing traflic, in opposite directions, a signal relay for the control of'each signal, two track relays for each section successively operated by the passage of a car or train through the section, means for energizing said track relays, each track relay controlling the signal relay for each signal governing trailic through the section; means for controlling each signal relay by the signal relay for the signal next in advance governing traffic in the same direction, an auxiliary relay for each signal relay adaptedwhen energized to render the latter inefl'ective to control the signal relay for the signal next in the rear,'a pickup and a holding circuit for each auxiliary relay, each pick-up circuit including a back contact of a track relay for the section through which the corresponding signal governs traiiic and a front .contact of the corresponding signal relay, and each holding circuit including a front contact of the auxiliary relay and the said back contact of the track relay and a source of current, and a branch around the said track relay contact for the holding circuit of each auxiliary relay, said branch including a back contact of the signal relay for the corresponding signal.

3. In combination, a stretch of railway track; signals located atintervals through the stretch for governing traffic in one direction, and other signals located at intervals for governing trafiic in the opposite direction, a signal relay for controlling each signal, track circuits for the stretch including track relays for controlling said signal relays, means for controlling the signal re-- lay for each signal by the signal relay for the signal next in advance governing traflic in the same direction, an auxiliary relay for each signal relay forrendering the latter ineffective to control the signal relay for the signal next in the rear, a pick-up circuit for each' auxiliary relay including a back contact of a track relay for the portion of the stretch directlygoverned by the corresponding signal and a front contact of the signal relay for such signal, and a holding circuit for each auxiliary relay including the said track relay back contact and a front contact of the auxiliary relay.

4. In combination, a stretch of railway track divided into sections, two track relays for each section adapted to be operated successively by the passage of a vehicle through the section, means for energizing said track relays; two signals for each section, one corresponding to one track relay and adapted to govern trafiic through the sectionin one direction, the other corresponding to the other track relay and adapted to govern trailic in the other direction; a signal relay for each signal and controlled by the track relays of the section through which the sigrelay and a back contact of the corresponding track relay, and a holding circuit for each auxiliary relay including the said track relay back contact and a front contact of the auxiliary relay, and a branch around the track relay contact in the holding circuit for each auxiliary relay, which branch includes a back contact of. the signal relay for the corresponding signa'l.

5. In combination, two successive sections of a railway track, a signal located adjacent the entrance end of each section, a signal relay for each signal for the control thereof, a line circuit for each signal relayextending through the corresponding section, track circuits for the sections including track relays for controlling the line circuits of the signal relays, means for controlling the line circuit for the section in the rear by the line circuit for the section in advance; and an auxiliary relay for removing the line circuit for the section in the rear from the control of the line circuit for the section in advance, a pick-up circuit for said auxiliary relay including a back contact of a track relay for,

the section in advance and a front contactiof the signal relay for the section in advance, and a holding circuit for said auxiliary relay including the said track relayback contact and a front contact of the auxiliary relay. I

6. In combination, two successive sections of a railway track, a signal located adjacent the entrance end of each section, a signal relay for each signal forthe control thereof, a line circuit for each signal relay extending through the corresponding section, two track relays for each section for controlling the line circuit of the signal relay for the section, said track relays being operated successively by the passage of a vehicle through said section, means for energizing said track relays, means for controlling the line circuit for'the section in the rear by the line circuit for the section in advance; and an auxiliary relay for removing the line circuit for the section in the rear from the control of the line circuit for the section in advance; a pick-up circuit for said auxiliary relay including a front contact of the signal relay for the section in advance and a back contact of that track relay for the section in advance, which is first operated when a vehicle passes into that section from the rear section, a holding circuit for said auxiliary relay including the said track relay back contact and a front contact of the auxiliary relay, and a branch for said holding circuit around the track relay back contact, said branch including a back contact of the signal relay for the section in advance.

7. In combination, a stretch of railway track, signals located at intervals for governing traflic in one direction through the stretch, a signal relay for each signal'for the control thereof, means for energizing said signal relays, track circuits for the stretch including track relays, each track relay being adapted, when affected by a train, to deenergize the signal relays for the signalsextending therefrom in the direction opposite to that in which the signals govern trailic, an auxiliary relay for each signal relay,

means controlled by each auxiliary relay when energized for energizing the signal relay for the signal next in the rear, a pickup circuit for each auxiliary relay including a back contact of the track relay for the portion of the stretch immediately governed by the corresponding signal and a front contact of the corresponding signal relay, and a holding circuit for each auxiliary relay including the said track relay back contact and a front contact of the auxiliary relay.

In testimony whereof I afiix my signature in presence of two witnesses.

HERBERT A. WALLACE.

Witnesses:

M. S. KIRKLAND, A. L. VENCILL. 

